Multilayer ceramic electronic component

ABSTRACT

A multilayer ceramic electronic component includes a ceramic body; and first and second external electrodes disposed on the ceramic body, wherein the first and second external electrodes include first and second conductive layers disposed on corners of the ceramic body, and first and second base electrodes covering the first and second conductive layers, respectively, and wherein a ratio, A 1 /A 2 , of an area, A 1 , of the first conductive layer disposed on the fifth surface or the second conductive layer disposed on the sixth surface of the ceramic body to an area, A 2 , of a cross-sectional surface of the ceramic body taken in the second direction and the first direction is in a range of 0.1 to 0.3.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims the benefit of priority to Korean PatentApplication No. 10-2019-0108007 filed on Sep. 2, 2019 in the KoreanIntellectual Property Office, the disclosure of which is incorporatedherein by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to a multilayer ceramic electroniccomponent.

BACKGROUND

With the trend for reducing the sizes of electronic products, amultilayer ceramic electronic component has been required to have areduced size and increased capacitance.

In accordance with the demand for a reduced size and increased capacityof a multilayer ceramic electronic component, an external electrode of amultilayer ceramic electronic component has also been designed to have areduced thickness.

To form an external electrode, a paste for an external electrode may beprepared by mixing a general conductive metal with glass, a base resin,an organic solvent, and the like, and the paste for an externalelectrode may be applied to both surfaces of a ceramic body, and a metalmay be sintered in the external electrode by baking-out the ceramicbody.

The paste for an external electrode may guarantee chip-sealingproperties and electrical connectivity with a chip using a conductivemetal as a main material, and using glass as an auxiliary material, thepaste may fill an empty space and may also provide cohesion forcebetween an external electrode and a chip when the metal is sintered andreduced.

However, as a multilayer ceramic electronic component has been designedto have a reduced size and high capacitance, an increased number oflayers of internal electrodes may be provided to secure capacitance, andaccordingly, an upper cover layer may be designed to have a reducedthickness.

Accordingly, when an external electrode is formed, an internal electrodemay be formed up to a region adjacent to a corner portion of a ceramicbody having a reduced thickness such that the internal electrode mayeasily be exposed to physical and chemical impacts.

Also, as an external electrode of the multilayer ceramic electroniccomponent has a reduced thickness, a thickness of an external electrodedisposed adjacent to a corner portion of a ceramic body may further bereduced such that corner coverage performance may degrade and a platingsolution may permeate through the corner.

In addition, in the case of an external electrode used in a highcapacity type capacitor, a material which can be sintered at lowtemperature may be used to reduce heat impact when an external electrodeis sintered. Particularly, glass softened at low temperature may berelatively vulnerable to acid resistance in a plating process. Due tothe above-described properties, when a plating layer is formedexternally of an external electrode, a plating solution may easilypermeate into a ceramic body, which may reduce moisture resistancereliability and may degrade product quality.

SUMMARY

An aspect of the present disclosure is to provide a multilayer ceramicelectronic component which may improve corner coverage performance of anexternal electrode to block a moisture permeation route such thatmoisture resistance reliability may improve and a band portion of anexternal electrode may have a reduced thickness.

According to an aspect of the present disclosure, a multilayer ceramicelectronic component includes a capacitance forming portion including adielectric layer and first and second internal electrodes stacked in afirst direction with the dielectric layer interposed therebetween; amargin portion disposed on both surfaces of the capacitance formingportion in a second direction; a cover portion disposed on both surfacesof the capacitance forming portion in the first direction; a ceramicbody having first and second surfaces opposing each other in the firstdirection, third and fourth surfaces opposing each other in the seconddirection, and fifth and sixth surfaces opposing each other in the thirddirection; and first and second external electrodes disposed on thefifth and sixth surfaces of the ceramic body, respectively, wherein thefirst and second external electrodes include first and second conductivelayers disposed on corners of the ceramic body, and first and secondbase electrodes covering the first and second conductive layers,respectively, and wherein a ratio, A₁/A₂, of an area, A₁, of the firstconductive layer disposed on the fifth surface or the second conductivelayer disposed on the sixth surface of the ceramic body to an area, A₂,of a cross-sectional surface of the ceramic body taken in the seconddirection and the first direction is in a range of 0.1 to 0.3.

According to another aspect of the present disclosure, a multilayerceramic electronic component includes a capacitance forming portionincluding a dielectric layer and first and second internal electrodesstacked in a first direction with the dielectric layer interposedtherebetween; a ceramic body having first and second surfaces opposingeach other in the first direction, third and fourth surfaces opposingeach other in a second direction, and fifth and sixth surfaces opposingeach other in a third direction; and first and second externalelectrodes disposed on the fifth and sixth surfaces of the ceramic body,respectively, wherein the first and second external electrodesrespectively include first and second conductive layers disposed on thefifth and sixth surfaces and extending in the third direction onto thefirst to fourth surfaces, the first and second conductive layers eachincluding an opening on the fifth surface or the sixth surfacepenetrating therethrough, wherein the first and second externalelectrodes further include first and second base electrodes covering thefirst and second conductive layers, and wherein a ratio, A₁/A₂, of anarea, A₁, of the first conductive layer disposed on the fifth surface orthe second conductive layer disposed on the sixth surface of the ceramicbody to an area, A₂, of a cross-sectional surface of the ceramic bodytaken in the second direction and the first direction is in a range of0.1 to 0.3.

BRIEF DESCRIPTION OF DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will be more clearly understood from the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a perspective diagram illustrating a multilayer ceramicelectronic component according to an exemplary embodiment of the presentdisclosure;

FIG. 2 is a perspective diagram illustrating a structure in which aconductive layer is disposed on a ceramic body of a multilayer ceramicelectronic component according to an exemplary embodiment of the presentdisclosure;

FIG. 3 is a perspective diagram illustrating a ceramic body of amultilayer ceramic electronic component according to an exemplaryembodiment of the present disclosure;

FIG. 4 is a cross-sectional diagram taken along line I-I′ in FIG. 1;

FIGS. 5 and 6 are diagrams illustrating a multilayer ceramic electroniccomponent, viewed in an A direction, according to an exemplaryembodiment of the present disclosure;

FIGS. 7 and 8 are diagrams illustrating a multilayer ceramic electroniccomponent, viewed in an A direction, according to another exemplaryembodiment of the present disclosure;

FIG. 9 is a perspective diagram illustrating a multilayer ceramicelectronic component according to another exemplary embodiment of thepresent disclosure;

FIG. 10 is a cross-sectional diagram taken along line II-II′ in FIG. 9;

FIG. 11 is a diagram illustrating a multilayer ceramic electroniccomponent, viewed in a B direction, according to an exemplary embodimentof the present disclosure; and

FIG. 12 is a diagram illustrating a multilayer ceramic electroniccomponent, viewed in a B direction, according to another exemplaryembodiment of the present disclosure.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be described asfollows with reference to the attached drawings.

It should be understood that the following exemplifying description ofthe invention is not intended to restrict the invention to specificforms of the present invention but rather the present invention is meantto cover all modifications, similarities and alternatives which areincluded in the spirit and scope of the present invention. The sameelements will be indicated by the same reference numerals.

For clarity of description, some elements may be omitted or brieflyillustrated, and thicknesses of elements may be magnified to clearlyrepresent layers and regions. The terms, “include,” “comprise,” “isconfigured to,” etc. of the description are used to indicate thepresence of features, numbers, steps, operations, elements, parts orcombination thereof, and do not exclude the possibilities of combinationor addition of one or more features, numbers, steps, operations,elements, parts or combination thereof.

In the diagram, an X direction may be defined as an L direction or alength direction, a Y direction may be defined as a W direction or awidth direction, and a Z direction may be defined as a T direction or athickness direction. The Z direction may also be defined as a firstdirection, the Y direction may also be defined as a second direction,and the X direction may also be defined as a third direction.

A value used to describe a parameter such as a 1-D dimension of anelement including, but not limited to, “length,” “width,” “thickness,”diameter,” “distance,” “gap,” and/or “size,” a 2-D dimension of anelement including, but not limited to, “area” and/or “size,” a 3-Ddimension of an element including, but not limited to, “volume” and/or“size”, and a property of an element including, not limited to,“roughness,” “density,” “weight,” “weight ratio,” and/or “molar ratio”may be obtained by the method(s) and/or the tool(s) described in thepresent disclosure. The present disclosure, however, is not limitedthereto. Other methods and/or tools appreciated by one of ordinary skillin the art, even if not described in the present disclosure, may also beused.

In the description below, a multilayer ceramic electronic component willbe described in accordance with an exemplary embodiment with referenceto FIGS. 1 to 4.

Referring to FIGS. 1 to 4, a multilayer ceramic electronic component inthe exemplary embodiment may include a capacitance forming portion α_(W)and α_(T) including a dielectric layer 111 and first and second internalelectrodes 121 and 122 stacked in a first direction (Z direction) withthe dielectric layer 111 interposed therebetween, a margin portion ddisposed on each of both surfaces of the capacitance forming portion inthe first direction, a cover portion c disposed on each of both surfacesof the capacitance forming portion, a ceramic body 110 having first andsecond surfaces S1 and S2 opposing each other in the first direction (Zdirection), third and fourth surfaces S3 and S4 opposing each other in asecond direction (Y direction), and fifth and sixth surfaces S5 and S6opposing each other in a third direction (X direction), and first andsecond external electrodes 131 and 132 disposed on the fifth surface S5and the sixth surface S6 of the ceramic body 110, respectively, and thefirst and second external electrodes 131 and 132 may include first andsecond conductive layers 131 a and 132 a disposed on corners of theceramic body 110, and first and second base electrodes 131 b and 132 bcovering the first and second conductive layers 131 a and 132 a,respectively.

When the first and second conductive layers 131 a and 132 a are disposedon corners of the ceramic body 110, respectively, the first and secondconductive layers 131 a and 132 a may protect internal electrodes fromexternal impacts.

To implement miniaturization and high capacitance of the multilayerceramic electronic component and to secure capacitance, a structure inwhich an increased number of layers of internal electrodes are providedand the cover portion having a reduced thickness is provided may beapplied. In this case, an internal electrode may be formed to a regionadjacent to a corner of the ceramic body, the region having a reducedthickness when an external electrode is formed, such that the internalelectrode may easily be exposed to physical and chemical impacts.

As an external electrode of the multilayer ceramic electronic componenthas been designed to have a reduced thickness, a thickness of theexternal electrode in a region adjacent to a corner of the ceramic bodymay further decrease such that corner coverage performance may degradeand a plating solution may permeate through the corner. Also, when glassis applied to the external electrode, the external electrode may berelatively vulnerable to acid resistance in a plating process. Due tothe above-described properties, when a plating layer is formed on anexternal electrode, a plating solution may easily permeate into aceramic body, which may reduce moisture resistance reliability and maydegrade product quality. In the multilayer ceramic electronic component100 in the exemplary embodiment, the first and second conductive layers131 a and 132 a may be disposed on corners of the ceramic body 110,respectively, to prevent degradation of moisture resistance reliabilitycaused by permeation of a plating solution and/or permeation ofmoisture.

According to the exemplary embodiment, a ratio (A₁/A₂) of an area A₁ ofthe first conductive layer 131 a or the second conductive layer 132 adisposed on the fifth surface S5 or the sixth surface S6 of the ceramicbody 110 to an area A₂ of a cross-sectional surface of the ceramic body110 taken in the second direction (Y direction) and the first direction(Z direction) may be in a range of 0.1 to 0.3.

The area A₂ of the cross-sectional surface of the ceramic body 110 takenin the second direction (Y direction) and the first direction (Zdirection) may be a value obtained by multiplying a width of the ceramicbody by a thickness thereof. For example, the value may be calculated by(d+α_(W)+d)×(c+α_(T)+c). Also, the area A₁ of the first conductive layer131 a or the second conductive layer 132 a disposed on the fifth surfaceS5 or the sixth surface S6 of the ceramic body 110 may refer to an areaof the first conductive layer 131 a or the second conductive layer 132 acovering the fifth surface S5 or the sixth surface S6, or an area of thefirst conductive layer 131 a or the second conductive layer 132 adisposed only on the fifth surface S5 or the sixth surface S6 of theceramic body 110. Thus, the area A₁ of the first conductive layer 131 aor the second conductive layer 132 a disposed on the fifth surface S5 orthe sixth surface S6 of the ceramic body 110 may refer to an area of thefirst conductive layer 131 a or the second conductive layer 132 adisposed on the surface of the ceramic body 110 in the second direction(Y direction) and the first direction (Z direction).

The multilayer ceramic electronic component 100 in the exemplaryembodiment may have improved corner coverage properties by configuringthe ratio (A₁/A₂) of the area A₁ of the first conductive layer 131 a orthe second conductive layer 132 a disposed on the fifth surface S5 orthe sixth surface S6 of the ceramic body 110 to the area A₂ of thecross-sectional surface of the ceramic body 110 taken in the seconddirection (Y direction) and the first direction (Z direction) to be inthe above-described range (e.g., 0.1 to 0.3).

In the exemplary embodiment, the ceramic body 110 may include thedielectric layer 111, the capacitance forming portion α_(W) and α_(T)including the first and second internal electrodes 121 and 122, themargin portion d disposed on each of both surfaces of the capacitanceforming portion α_(W) and α_(T) in the second direction (Y direction),and the cover portion c disposed on each of both surfaces of thecapacitance forming portion α_(W) and α_(T) in the first direction (Zdirection).

A shape of the body 110 may not be limited to any particular shape, butas illustrated in the diagram, the body 110 may have a hexahedral shapeor a shape similar to a hexahedron. Due to contraction of a ceramicpowder included in the body 110 during a sintering process, the body 110may have substantially a hexahedral shape although the hexahedral shapemay not be an exact hexahedron formed by straight lines. The ceramicbody 110 may have the first and second surfaces S1 and S2 opposing eachother in a thickness direction (Z direction), the third and fourthsurfaces S3 and S4 connected to the first and second surfaces S1 and S2and opposing each other in a width direction (Y direction), and thefifth and sixth surfaces S5 and S6 connected to the first and secondsurfaces S1 and S2 and the third and fourth surfaces S3 and S4 andopposing each other in a length direction (X direction).

The ceramic body 110 may be formed by alternately layering a ceramicgreen sheet on which the first internal electrode 121 is printed on thedielectric layer 111 and a ceramic green sheet on which the secondinternal electrode 122 is printed on the dielectric layer 111 in thethickness direction (Z direction).

In the capacitance forming portion α_(W) and α_(T), the dielectric layer111 and the first and second internal electrodes 121 and 122 may bealternately stacked. The plurality of the dielectric layers 111 includedin the capacitance forming portion α_(W) and α_(T) may be in a sinteredstate, and a boundary between adjacent dielectric layers 111 may beintegrated such that it may be difficult to identify the boundarywithout using a scanning electron microscope (SEM).

In the exemplary embodiment, a material of the dielectric layer 111 maynot be limited to any particular material as long as sufficientcapacitance can be obtained. For example, the dielectric layer 111 maybe formed using a barium titanate material, a perovskite materialcompound with lead, a strontium titanate material, or the like.

Also, as the material of the dielectric layer 111, a barium titanate(BaTiO₃) powder, or the like, including various ceramic additives,organic solvents, coupling agents, dispersing agents, and the like, maybe used depending on an intended purpose.

For example, the dielectric layer 111 may be formed by disposing aplurality of ceramic sheets formed by applying slurry including powdersuch as barium titanate (BaTiO₃) on a carrier film and drying theslurry. The ceramic sheet may be formed by manufacturing slurry formedfrom a mixture of a ceramic powder, a binder, and a solvent andmanufacturing a sheet having a thickness of a several μm using theslurry through a doctor blade process, but an exemplary embodimentthereof is not limited thereto.

In the multilayer ceramic electronic component in the exemplaryembodiment, the internal electrodes 121 and 122 may be alternatelystacked to oppose each other with the dielectric layer 111 interposedtherebetween. The internal electrodes 121 and 122 may include the firstand second internal electrodes 121 and 122 alternately disposed tooppose each other with the dielectric layer 111 interposed therebetween.

The first internal electrode 121 may be exposed to one surface of theceramic body 110 taken in the third direction (X direction), and aportion of the first internal electrode 121 exposed to the one surfacetaken in the third direction (X direction) may be connected to the firstexternal electrode 131. The second internal electrode 122 may be exposedto the other surface of the ceramic body 110 taken in the thirddirection (X direction), and a portion of the second internal electrode122 exposed to the other surface taken in the third direction (Xdirection) may be connected to the second external electrode 132. Thefirst and second internal electrodes 121 and 122 may be electricallyseparated from each other by the dielectric layer 111 interposedtherebetween.

A material of the first and second internal electrodes 121 and 122 maynot be limited to any particular material, and may be formed using aconductive paste including one or more materials from among silver (Ag),palladium (Pd), nickel (Ni), gold (Au), platinum (Pt), copper (Cu), tin(Sn), tungsten (W), titanium (Ti), and alloys thereof. As a method ofprinting the conductive paste, a screen-printing method, a gravureprinting method, or the like, may be used, but the printing method isnot limited thereto.

In the multilayer ceramic electronic component, the margin portion d maybe disposed on each of both surfaces of the capacitance forming portionα_(W) and α_(T) in the second direction. The margin portion d may bedisposed on each of both surfaces of the capacitance forming portionα_(W) and α_(T) in the second direction (Y direction) perpendicular tothe first and third directions (Z direction and X direction,respectively). The margin portion d may prevent damages to the internalelectrode caused by physical or chemical stress.

The margin portion d may be formed of an insulating material, and may beformed of a ceramic material such as barium titanate, or the like. Inthis case, the margin portion d may include a ceramic material the sameas a material included in the dielectric layer 111, or may be formed ofa material the same as a material of the dielectric layer 111.

A method of forming the margin portion d is not limited any particularmethod. For example, the margin portion d may be formed by forming amargin region on a circumference portion other than a portion of theinternal electrode connected to the external electrode by forming anarea of the dielectric layer included in the capacitance forming portionα_(W) to be greater than an area of the internal electrode, by applyingslurry including ceramic, or by attaching a dielectric sheet on each ofboth surfaces of the capacitance forming portion α_(W) in the seconddirection (Y direction).

The multilayer ceramic electronic component in the exemplary embodimentmay include the cover portion c. The cover portion c may be disposed onan outermost region of the first and second internal electrodes 121 and122. The cover portion c may be disposed on a lowermost internalelectrode and on an uppermost internal electrode. In this case, thecover portion c may be formed of a composition the same as a compositionof the dielectric layer 111, and may be formed by layering at least oneor more dielectric layers on the uppermost internal electrode and thelowermost internal electrode. The cover portion c may prevent damage tothe internal electrode caused by physical or chemical stress.

In the multilayer ceramic electronic component in the exemplaryembodiment, the first external electrode 131 and the second externalelectrode 132 may be disposed on both surfaces of the ceramic body inthe third direction (X direction). The first external electrode 131 maybe electrically connected to the first internal electrode 121, and thesecond external electrode 132 may be electrically connected to thesecond internal electrode 122.

The first and second external electrodes 131 and 132 may include thefirst and second conductive layers 131 a and 132 a disposed on cornersof the ceramic body 110 and the first and second base electrodes 131 band 132 b covering the first and second conductive layers 131 a and 132a. FIG. 2 is a perspective diagram illustrating a structure in whichonly the first and second conductive layers 131 a and 132 a are disposedin the ceramic body 110. Referring to FIG. 2, the first conductive layer131 a may be disposed on a corner at which the fifth surface S5 meetsthe first to fourth surfaces (S1 to S4). Also, the second conductivelayer 132 a may be disposed on a corner at which the sixth surface S6meets the first to fourth surfaces S1 to S4.

In an exemplary embodiment, the first conductive layer 131 a may extendto the fifth surface S5 of the ceramic body 110 and the first to fourthsurfaces S1 to S4 in contact with the fifth surface S5. Also, the secondconductive layer 132 a may extend to the sixth surface S6 of the ceramicbody 110 and the first to fourth surfaces S1 to S4 in contact with thesixth surface S6. Referring to FIG. 2, the first conductive layer 131 amay be disposed on a corner of the fifth surface S5 of the ceramic body110, and may extend to the first to fourth surfaces S1 to S4 of theceramic body 110. The second conductive layer 132 a may be disposed on acorner of the sixth surface S6 of the ceramic body 110 and may extend tothe first to fourth surfaces S1 to S4 of the ceramic body 110.Accordingly, when the first and second conductive layers 131 a and 132 aare configured to cover each corner of the multilayer ceramic electroniccomponent 100, corners of the multilayer ceramic electronic component100, vulnerable regions of the multilayer ceramic electronic component100 may be protected.

As in the exemplary embodiment described above, when the firstconductive layer 131 a and the second conductive layer 132 a extend tothe first to fourth surfaces S1 to S4 of the ceramic body 110, and thefirst conductive layer 131 a and the second conductive layer 132 a aredisposed excessively adjacent to each other, shorts may occur betweenthe components. Thus, the first conductive layer 131 a and the secondconductive layer 132 a may be configured to be spaced apart from eachother. A spacing distance between the first conductive layer 131 a andthe second conductive layer 132 a is not limited to any particular size.For example, the first conductive layer 131 a and the second conductivelayer 132 a may be spaced apart from each other with a distance equal toor greater than 1/20 times and less than 1 time a length of the ceramicbody 110, but an exemplary embodiment thereof is not limited thereto.

In an exemplary embodiment, an end of the first conductive layer 131 adisposed on the fifth surface S5 of the ceramic body 110 may be incontact with the first internal electrode 121. Also, an end of thesecond conductive layer 132 a disposed on the sixth surface S6 of theceramic body 110 may be in contact with the second internal electrode122. The configuration in which the first and second conductive layers131 a and 132 a are in contact with the first internal electrode 121 andthe second internal electrode 122, respectively, may indicate that thefirst conductive layer 131 a may be electrically connected to the firstinternal electrode 121 and that the second conductive layer 132 a may beelectrically connected to the second internal electrode 122. Theconfiguration may indicate that a portion of the first internalelectrode 121 exposed through the fifth surface S5 of the ceramic body110 may be physically in contact with the first conductive layer 131 a,and a portion of the second internal electrode 122 exposed through thesixth surface S6 of the ceramic body 110 may be physically in contactwith the second conductive layer 132 a.

Referring to FIG. 4, in the aforementioned exemplary embodiment, thefirst conductive layer 131 a may be in contact with the first internalelectrode 121 within the capacitance forming portion α_(T). The secondconductive layer 132 a may be in contact with the second internalelectrode 122 within the capacitance forming portion α_(T). Whenmoisture permeate into the multilayer ceramic electronic component 100,a region between the capacitance forming portion α_(T) and the coverportion c may be a vulnerable point in terms of the structure of themultilayer ceramic electronic component 100. That is because a point atwhich outermost internal electrodes 121 and 122 meet the cover layer cmay have the least mechanical strength due to a difference in sinteringreduction rate between the dielectric layer 111 and the internalelectrodes 121 and 122. In the multilayer ceramic electronic component100 in the exemplary embodiment, the first conductive layer 131 a andthe second conductive layer 132 a may be configured to be in contactwith the first internal electrode 121 and the second internal electrode122, respectively, such that corner coverage of the point at which thecapacitance forming portion α_(T) meets the cover portion c may improve,and accordingly, a moisture permeation route may be block in advance.

The first base electrode 131 b and the second base electrode 132 b ofthe multilayer ceramic electronic component 100 in the exemplaryembodiment may cover the first conductive layer 131 a and the secondconductive layer 132 a, respectively. The configuration in which thebase electrodes 131 b and 132 b may cover the conductive layers 131 aand 132 a may indicate that the base electrodes 131 b and 132 b may bedisposed such that the conductive layers 131 a and 132 a may not beexternally exposed, and that the first conductive layer 131 a and thesecond conductive layer 132 a may be disposed in the first externalelectrode 131 and the second external electrode 132, respectively, suchthat only the first base electrode 131 b and the second base electrode132 b may be visible from the outside.

In an exemplary embodiment, a central portion of the fifth surface S5 ofthe ceramic body 110 of the multilayer ceramic electronic component 100may be in contact with the first base electrode 131 b, and a centralportion of the sixth surface S6 may be in contact with the second baseelectrode 132 b. The configuration in which the fifth surface S5 of theceramic body 110 may be in contact with the first base electrode 131 bmay indicate that the first conductive layer 131 a may not be disposedon the central portion of the fifth surface S5 of the ceramic body 110,and the configuration in which the sixth surface S6 of the ceramic body110 may be in contact with the second base electrode 132 b may indicatethe structure in which the second conductive layer 132 a may not bedisposed on a central portion of the sixth surface S6 of the ceramicbody 110. In the exemplary embodiment, the first conductive layer 131 aand the second conductive layer 132 a may be disposed on corners of theceramic body 110, the first base electrode 131 b may cover the firstconductive layer 131 a, and the second base electrode 132 b may coverthe second conductive layer 132 a such that moisture resistancereliability may improve, electrical conductivity may be maintained, andperformance of the multilayer ceramic electronic component may bemaintained.

FIGS. 5 to 8 are diagrams illustrating a multilayer ceramic electroniccomponent 100 illustrated in FIG. 1, viewed in an A direction. Referringto FIGS. 5 and 6, in an exemplary embodiment, each of regions of thefirst and second base electrodes 131 b and 132 b in which the first andsecond conductive layers 131 a and 132 a are not disposed in the thirddirection (X direction) in the ceramic body 110 may have a quadrangularshape. When each of the regions of the first and second base electrodes131 b and 132 b in which the first and second conductive layers 131 aand 132 a are not disposed has a quadrangular shape, an area of externalelectrode corner coverage may be uniformly formed such that an effect ofpreventing a plating solution from permeating may improve.

In one exemplary embodiment, a maximum width (w) in the Y direction anda maximum height (h) in the Z direction of an area of each of the firstand second base electrodes, on which the first and second conductivelayers are not disposed in the third direction, may be less than amaximum width in the Y direction and a maximum height (α_(T)) in the Zdirection of the capacitance forming portion, respectively. Such widthsand heights may be may be measured by a standard method that will beapparent to and understood by one of ordinary skill in the art.

Referring to FIGS. 7 and 8, in the multilayer ceramic electroniccomponent 100 in another exemplary embodiment, each of regions of thefirst and second base electrodes 131 b and 132 b in which the first andsecond conductive layers 131 a and 132 a are not disposed in the thirddirection (X direction) in the ceramic body 110 may have a circularshape. When each of the regions of the first and second base electrodes131 b and 132 b in which the first and second conductive layers 131 aand 132 a are not disposed has a circular shape, a moisture permeationroute may be reduced such that an effect of preventing a platingsolution from permeating may improve.

In an exemplary embodiment, the first conductive layer 131 a, the secondconductive layer 132 a, the first base electrode 131 b, and the secondbase electrode 132 b may include the same conductive metal. As in theexemplary embodiment, when the first conductive layer 131 a, the secondconductive layer 132 a, the first base electrode 131 b, and the secondbase electrode 132 b include the same conductive metal, cohesionproperties between the conductive layer and the base electrode mayimprove such that permeation of moisture may be prevented effectively.

In another exemplary embodiment, the first conductive layer 131 a, thesecond conductive layer 132 a, the first base electrode 131 b, and thesecond base electrode 132 b may include a conductive metal, and anaverage particle size of a conductive metal included in the first andsecond base electrodes 131 b and 132 b may be greater than an averageparticle size of a conductive metal included in the first and secondconductive layers 131 a and 132 a. An average particle size of theconductive metal may refer to a particle size of D50, and may bemeasured using a particle size analyzer such as SALD-7101 of Shimadzu.When an average particle size of a conductive metal included in thefirst and second conductive layers 131 a and 132 a is less than anaverage particle size of a conductive metal included in the first andsecond base electrodes 131 b and 132 b, the first conductive layer 131 aand the second conductive layer 132 a may have a more cohesive structuresuch that performance of preventing moisture permeation may be improved.Also, cohesiveness between the first and second conductive layers 131 aand 132 a and the first and second base electrodes 131 b and 132 b mayincrease such that moisture resistance reliability may be improved.

In an exemplary embodiment, the first conductive layer 131 a, the secondconductive layer 132 a, the first base electrode 131 b, and the secondbase electrode 132 b may include copper (Cu). The first conductive layer131 a, the second conductive layer 132 a, the first base electrode 131b, and the second base electrode 132 b may include copper (Cu) the most,but an exemplary embodiment thereof is not limited thereto. For example,the first conductive layer 131 a, the second conductive layer 132 a, thefirst base electrode 131 b, and the second base electrode 132 b may beformed using conductive paste including one or more materials from amongnickel (Ni), tin (Sn), palladium (Pd), platinum (Pt), gold (Au), silver(Ag), tungsten (W), titanium (Ti), lead (Pb), and alloys thereof andglass.

A method of forming the first conductive layer 131 a, the secondconductive layer 132 a, the first base electrode 131 b, and the secondbase electrode 132 b may not be limited to any particular method. Forexample, the first conductive layer 131 a, the second conductive layer132 a, the first base electrode 131 b, and the second base electrode 132b may be formed by dipping the ceramic body in the conductive pasteincluding a conductive metal and glass, by printing the conductive pasteon a surface of the ceramic body by a screen printing method or agravure printing method, by applying the conductive paste on a surfaceof the ceramic body, or by transcribing a dried film formed by dryingthe conductive paste on the ceramic body, but an example of the methodis not limited thereto. As the first conductive layer 131 a, the secondconductive layer 132 a, the first base electrode 131 b, and the secondbase electrode 132 b are formed using the conductive paste describedabove, sufficient conductivity may be maintained, and cohesiveness ofthe external electrode may increase due to the added glass such thatpermeation of a plating solution and/or moisture may be preventedeffectively.

A glass composition included in the first conductive layer 131 a, thesecond conductive layer 132 a, the first base electrode 131 b, and thesecond base electrode 132 b may include a mixture of various oxides, andmay include one or more selected from a group consisting of siliconoxide, boron oxide, aluminum oxide, transition metal oxide, alkalinemetal oxide, and alkaline earth metal oxide. Transition metal may beselected from a group consisting of zinc (Zn), titanium (Ti), copper(Cu), vanadium (V), manganese (Mn), iron (Fe), and nickel (Ni), alkalinemetal may be selected from a group consisting of lithium (Li), natrium(Na), and kalium (K), and alkaline earth metal may be selected from agroup consisting of magnesium (Mg), calcium (Ca), strontium (Sr), andbarium (Ba).

In an another exemplary embodiment, a multilayer ceramic electroniccomponent may include a first terminal electrode 231 c disposed on thefirst base electrode 131 b and a second terminal electrode 232 cdisposed on the second base electrode 132 b. FIG. 9 is a perspectivediagram illustrating a multilayer ceramic electronic component 200according to an exemplary embodiment, and FIG. 10 is a cross-sectionaldiagram taken along line II-II′ in FIG. 9. Referring to FIGS. 9 and 10,the first terminal electrode 231 c of a first external electrode 231 andthe second terminal electrode 232 c of a second external electrode 232may cover a first base electrode 231 b and a second base electrode 232b, respectively. The first base electrode 231 b and the second baseelectrode 232 b may cover a first conductive layer 231 a and a secondconductive layer 232 a, respectively, which are disposed on corners of aceramic body 210.

In an exemplary embodiment, the first and second terminal electrodes 231c and 232 c may be formed by a plating process. The first and secondterminal electrodes 231 c and 232 c may be formed by a sputteringprocess or an electric deposition process, but an exemplary embodimentthereof is not limited thereto.

The first and second terminal electrodes 231 c and 232 c may includenickel (Ni) the most, but an exemplary embodiment thereof is not limitedthereto. The first and second terminal electrodes 231 c and 232 c mayinclude nickel (Ni), tin (Sn), copper (Cu), palladium (Pd), platinum(Pt), gold (Au), silver (Ag), tungsten (W), titanium (Ti), lead (Pb),and alloys thereof. By including the first and second terminalelectrodes 231 c and 232 c, mounting properties with a substrate,structural reliability, durability against external impacts, heatresistance properties and/or an equivalent series resistance (ESR) valuemay improve.

Table 1 below relates to a thickness of the external electrode of acorner of the ceramic body based on whether the first and secondconductive layers are applied and according to a ratio of an area of thefirst and second conductive layers (A₁) to an area of a cross-sectionalsurface of the ceramic body (A₂). The thicknesses and areas described inthe Table 1 may be may be measured or calculated by a standard methodthat will be apparent to and understood by one of ordinary skill in theart.

TABLE 1 Thickness of External Whether Ratio of Electrode ThicknessConductive Conductive Disposed of External Layer is Layer Area on CornerElectrode Classification disposed (%) , A₁/A₂ (μm) (μm) Comparative x 07 290 Example 1 Embodiment 1 ∘ 10 15 296 Embodiment 2 20 22 299Embodiment 3 30 25 323 Comparative 40 26 380 Example 2

As indicated in Table 1, as compared to comparative example 1 in whichthe first and second conductive layers are not disposed, in embodiments1 to 3, the thickness of the external electrode disposed on the cornerof the ceramic body may be increased without affecting a thickness ofthe external electrode. Also, when an area of the conductive layerexceeds 30%, an overall thickness of the external electrode may greatlyincrease such that it may be difficult to reduce a size of thecomponent.

According to the aforementioned exemplary embodiments, the multilayerceramic electronic component which may improve corner coverageperformance of the external electrode may be provided.

Also, the multilayer ceramic electronic component having improvedmoisture resistance reliability may be provided.

Further, the multilayer ceramic electronic component in which a moisturepermeation route may be blocked and a band portion of the externalelectrode may have a reduced thickness may be provided.

While the exemplary embodiments have been shown and described above, itwill be apparent to those skilled in the art that modifications andvariations could be made without departing from the scope of the presentinvention as defined by the appended claims.

What is claimed is:
 1. A multilayer ceramic electronic component,comprising: a capacitance forming portion including a dielectric layerand first and second internal electrodes stacked in a first directionwith the dielectric layer interposed therebetween; a margin portiondisposed on both surfaces of the capacitance forming portion in a seconddirection; a cover portion disposed on both surfaces of the capacitanceforming portion in the first direction; a ceramic body having first andsecond surfaces opposing each other in the first direction, third andfourth surfaces opposing each other in the second direction, and fifthand sixth surfaces opposing each other in the third direction; and firstand second external electrodes disposed on the fifth and sixth surfacesof the ceramic body, respectively, wherein the first and second externalelectrodes respectively include first and second conductive layersdisposed on corners of the ceramic body, and first and second baseelectrodes covering the first and second conductive layers,respectively, and wherein a ratio, A₁/A₂, of an area, A₁, of the firstconductive layer disposed on the fifth surface or the second conductivelayer disposed on the sixth surface of the ceramic body to an area, A₂,of a cross-sectional surface of the ceramic body taken in the seconddirection and the first direction is in a range of 0.1 to 0.3.
 2. Themultilayer ceramic electronic component of claim 1, wherein the firstconductive layer extends onto the fifth surface and the first to fourthsurfaces in contact with the fifth surface of the ceramic body, andwherein the second conductive layer extends onto the sixth surface andthe first to fourth surfaces in contact with the sixth surface of theceramic body.
 3. The multilayer ceramic electronic component of claim 1,wherein the first and second conductive layers extending to the first tofourth surfaces are spaced apart from each other.
 4. The multilayerceramic electronic component of claim 1, wherein ends of the first andsecond conductive layers disposed on the fifth and sixth surfaces,respectively, are in contact with the first internal electrode or thesecond internal electrode.
 5. The multilayer ceramic electroniccomponent of claim 1, wherein central portions of the fifth and sixthsurfaces of the ceramic body are in contact with the first and secondbase electrodes, respectively.
 6. The multilayer ceramic electroniccomponent of claim 1, wherein an area of each of the first and secondbase electrodes on which the first and second conductive layers are notdisposed in the third direction in the ceramic body has a quadrangularshape.
 7. The multilayer ceramic electronic component of claim 1,wherein an area of each of the first and second base electrodes on whichthe first and second conductive layers are not disposed in the thirddirection in the ceramic body has a circular shape.
 8. The multilayerceramic electronic component of claim 1, wherein the first conductivelayer, the second conductive layer, the first base electrode, and thesecond base electrode include a same conductive metal.
 9. The multilayerceramic electronic component of claim 1, wherein the first conductivelayer, the second conductive layer, the first base electrode, and thesecond base electrode include a conductive metal, and wherein an averageparticle size of the conductive metal included in the first and secondbase electrodes is greater than an average particle size of theconductive metal included in the first and second conductive layers. 10.The multilayer ceramic electronic component of claim 1, wherein thefirst conductive layer, the second conductive layer, the first baseelectrode, and the second base electrode include copper.
 11. Themultilayer ceramic electronic component of claim 1, further comprising:first and second terminal electrodes covering the first and second baseelectrodes.
 12. The multilayer ceramic electronic component of claim 1,wherein a maximum width in the second direction and a maximum height inthe first direction of an area of each of the first and second baseelectrodes, on which the first and second conductive layers are notdisposed, are less than a maximum width in the second direction and amaximum height of the capacitance forming portion in the firstdirection, respectively.
 13. A multilayer ceramic electronic component,comprising: a capacitance forming portion including a dielectric layerand first and second internal electrodes stacked in a first directionwith the dielectric layer interposed therebetween; a ceramic body havingfirst and second surfaces opposing each other in the first direction,third and fourth surfaces opposing each other in a second direction, andfifth and sixth surfaces opposing each other in a third direction; andfirst and second external electrodes disposed on the fifth and sixthsurfaces of the ceramic body, respectively, wherein the first and secondexternal electrodes respectively include first and second conductivelayers disposed on the fifth and sixth surfaces and extending in thethird direction onto the first to fourth surfaces, the first and secondconductive layers each including an opening on the fifth surface or thesixth surface penetrating therethrough, wherein the first and secondexternal electrodes further include first and second base electrodescovering the first and second conductive layers, and wherein a ratio,A₁/A₂, of an area, A₁, of the first conductive layer disposed on thefifth surface or the second conductive layer disposed on the sixthsurface of the ceramic body to an area, A₂, of a cross-sectional surfaceof the ceramic body taken in the second direction and the firstdirection is in a range of 0.1 to 0.3.
 14. The multilayer ceramicelectronic component of claim 13, further comprising: a margin portiondisposed on both surfaces of the capacitance forming portion in thesecond direction; and a cover portion disposed on both surfaces of thecapacitance forming portion in the first direction.
 15. The multilayerceramic electronic component of claim 13, wherein the first and secondconductive layers extending to the first to fourth surfaces are spacedapart from each other.
 16. The multilayer ceramic electronic componentof claim 13, wherein ends of the first and second conductive layersdisposed on the fifth and sixth surfaces, respectively, are in contactwith the first internal electrode and the second internal electrode,respectively.
 17. The multilayer ceramic electronic component of claim13, wherein an area of each of the first and second base electrodes onwhich the first and second conductive layers are not disposed in thethird direction in the ceramic body has a quadrangular shape.
 18. Themultilayer ceramic electronic component of claim 13, wherein an area ofeach of the first and second base electrodes on which the first andsecond conductive layers are not disposed in the third direction in theceramic body has a circular shape.
 19. The multilayer ceramic electroniccomponent of claim 13, wherein the first conductive layer, the secondconductive layer, the first base electrode, and the second baseelectrode include a conductive metal, and wherein an average particlesize of the conductive metal included in the first and second baseelectrodes is greater than an average particle size of the conductivemetal included in the first and second conductive layers.
 20. Themultilayer ceramic electronic component of claim 13, wherein the firstconductive layer, the second conductive layer, the first base electrode,and the second base electrode include copper.